Luminant in electric incandescent lamps.



No. 844,778. PATENTED FEB. 19, 1907. F. M. F. GAZIN. LUMINANT INELECTRIC INGANDESGENT LAMPS.

APPLICATION FILED JULY 27, 1899.

FRANCIS MJFPCAZIN, OF IIOBOKEN, NEW JERSEY.

LUMINANT IN ELECTFHCINCANDESCENT LAMPS.

Specification of Letters Patent.

Patented Feb. 19, 1907.

Application filed July 27,1899. Serial No. 725.283.

To all; whom, it may concern:

Be it known that I, FRANCIS M. F. UAZIN,

. a citizen of the United States, residing at 1108 Bloomfield street,city of lloboken, in the county of Hudson and State of New Jersey, haveinvented certain new and useful Improvements in for Luminants inElectric Incandescent Lamps, of which the following is a specification.

The purpose of this present application is of the same character and inthe same relation to my Patents No. 523,460, of July 24., 1894, and No.523,461, of same date, and No. 566,285, of August 18, 1896; No. 020,640,of March 7, and Nos. 621,291 and 621,292, of March 14, 1899, and No.640,620, of January 2, 1900, and to all the applications therefor,

as my application of February 2, 1899, Se-

rial No. 704.,2l8-namel v, to obtain patent on certain modifications inthe processes of manufacturing electric incandescent lamps invented byme and on the lamps that are the products of such manufacture, whichprocesses and lamps were alluded to in these patents, but were notexplicitly enough specitied and not suflicientlydisclosed forformulating on the said specifications and disclosures the proper claimsfor their protection by patent, though the invention as such or in itsessential characteristics 'has then and I there been set forth, and, asconditioned on 1 such identity of pur ose and similarity ofsubiect-matter, as we 1 as to facilitate a clear and full understandingof the in'iprovement claimed by this application, I have selected fromthese my prior applications a few parts to recite, and in special docsapplicant proose to congregate all matter herein which as been objectedto as new in his application Serial No. 704,218, in order to preservethe continuity as between this application and its redccessors by thesame applicant n my prior application. Serial No. 704,218, filedFebruary 2, 1899, and since renewed on A ril 15, 1902, as Serial No.102,993, and on W ich Patent No. 835,938 was issued on November 13,1906, I have described certain improvements in the luminant forincandescent electric lamps consisting of a metal core covered with afilm of metal having less ailinity for oxygen than the metal of the coreembedded in rare-metal oxids, which under the influence of heatgenerated by the passage of electric current become luminous.

This, my present invention, relates to cortain improvements upon thestructure disclosed in said previous application in that I now prefer toconstruct the core of metal or metals of the rutlienium-osmium class andpreferably of an alloy of two or more such metals, the same to be coatedwith alloy of metal of less affinity for oxygen than the core metal.

It is my intention, therefore, to secure'patcnt for using, incombination with a filament proper, an accessory conducting part orlayer such as mentioned in my Patent No. 621,291 in the statement, page3, lines 111, &c., where the statement is made that the essential con(litions for practical light increase are that between these (surface)oxide and the filament (proper) there be intercohesiveness and thatfilament and oXids be insulated by an intermediate stratum as not todeteriorate one another, and the selection of material for theintermediate layer is limited only by functional requirements, as oftenexplained, the base metals of the oxids of the surface layer beingfunctionally fit and adapted.

l have used hereabove the Word alloy in its older sense, specifying ametallic compound in portions of the single metals cntircly independentof their proportional atomic Weight.

My invention further consists in the construction, arrangement. andcombination of the several parts of which it is com osed, and which willbe hereinafter more fu .y described and claimed.

In the matter of visible form of my im proved luminant I have discloseddifferent forms of luminous bodies, according to the functions assignedthereto and to the parts thereof, any one of which forms may beselected. All and every form which ada ts itself to the functionalconditions assigned to the different improved parts is embraced in myimprovements.

The figure re resents a view of the luminant as claime inelosed in glassparts and equipped for current connection in a similar manner as by meshown in my prior applica- 'tions.

The symbols marked on said figure indicate parts as follows, namely:

1 and 2 indicate the inleadiug and outleading wires. r

3 indicates the main all-glass base part, with the following subparts.namely: 3*, the reflecting top face of such base: 3*. the open tubularcollar, intendedto hold hermetically the it per part; 3, the invertedtest-tube, 1 I alloyed with one or more of these metals sealerhermetically at both ends, though erforated by an in or out leadingwire, or by both, by means of fused glass-powder, held in place at bothends by collars of the base 3; 3, the smaller and screw-slumped end ofthe main all-glass base 3; 3, the openings in the all-glass base 3 forair circulation and the differential cooling of 3,

4 indicates one and 4 the other pole-cap of the lamp.

5 and 0 indicate an inner and an outerhermetically-sealed air-exlmustedglass bulbs, with 5 a perforation of 5 for the purpose of simultaneousair evacuation.

11 indicate the exposed parts of the in' and out leading wires.

12 indicates the terminals of the luminant 15.

15 indicates in exaggerated size and in an exterior view the luminant,the composition and construction of which is described in thisspecification.

In regard to thc-luminant thus shown I refer to my general statements inmy Patent No. 620,640, in line 96, on page 1, describing the same in thematter of general structure as follows: The luminous body as such is anintegrally-compound body or an integral structure of differentmaterials, though of different composition chemically, physically inimmediate and permanent contact with one another; and in lines 88, &c.,on page 2: The dimensions that lam dealing with in making up theluminous body or structure are altogether extren'tely minute, and itscomponent parts or elements or materials can 111 consequence not beotherwise than of extremely minute dimensions and cannot be ofthicknesses that can by common means be measured, though in still sominute thicknesses they by their chemical and distinct nature performthe function to them assigned; and in regard to the state that I usemetals in when they enter into the construction or composition of myimproved luminants I refer to my Patent No. 640,620, issued on January2, 1900, or to my application of March 21, 1899, (forty-eight days priorto this application) viz., to the fifty-fourth line on second page ofthe said patent, which reads as follows: l/Vhere a metal core is used, Icite the use of an alloy of the metals of the platinum class-such asplatinum, paladium, rhodium, ruthenium, osmium, and iridium--as occursin nature (iridiosmine) or artificially produced, with suitableproportions of all or of some, and when in my prior a plications Idisclosed the selection. of a metalifor making therewith a filament ofthe highest practicable fusionpoint, or of a metal of theruthenitun-osmium class, I intended to use the metals of this classindiscriminately, singly or together, viz., as alloys; and in one of mymethods another metal of a lower point of fusion and the general innerstructure of my improved electric incandescent lamp as herein claimedhas been by me disclosed in my Patent No. 620,640 and illustrated asFig. 8 to the said patent, such figure being described, (page 4, line2): Fig. 8 represents the luminous body in my improved lam with afilament of curvatures (longitudina ly, such as loops, &c. as nowcommonly used and with successive layers of material adapted to suchfilament and curvatures.

Fig. 2, representing a luminant exclusively, illustrates the same asconsisting of a spiral -t'ormed metallic currcntconducting core, of alayer or layers of metals, be they plated singly or as alloys unto thesaid core, and modifying. the spiral form of the metal core as such intoa simple cylindrical form for the luminant as a whole, and a surfacecoating, which may consist of metal of less allinity for oxygen thanthat of the core metal or metals and may have an oxidized surface ornot.

1 do not wish to be understood as limiting it in any way to thetheoretical statement that the rare-metal oxids become in themselvesconductive by heat and subsequently accessory conductors, as the natureof my invention is entirely independent of whether or not such be thecase, it being based merely upon the construction employed whereby therare-nLctal oxids, from whatever cause it may be, become luminous whenthe main conductive element is connected in circuit with the propervoltage; nor do I wish it to be understood, contrary to my conception ofmy invention, that the application of an embedding coat or of a surfacecoating of rare-metal oxids be limited to any kind of my infusiblemetalfilaments exclusively, but that such coat or coating is applied by me aswell to a metallic core as well as to such a core protected by ametallic chemical insulating coat, since, as fully explained in myPatent No. 620,640, page 2, lines 99 and following, there is undercurrent applied an automatic reaction between a conducting-core whichhas allinity for oxygen, on the one hand, and rare-metal oxids, on theother hand, both being in ade quate proportion, by which reaction a partof the oxids is reduced to metal and as such' then forms a chemicalinsulating metallic stratum or intermediate coating.

The filament as proposed in this application consists of metal of therutheniumosmium class or of an alloy of said metals, the metals of thesaid class bein confined to those combining a high point of fusion withallinity for oxygen and including Wolfram, uranium, manganum, rhodium,iridium, and thorium, as well as others of like characteristics.

A further characteristic quality of these ICC metals is theirbrittleness or their capability of being powdered in their normal pureor native state; but'it should not be overlooked that while I-havedivided .out of this applica- -ural qualities or by artificialpreparation thereof, such as reducing excessive conductivity b powderingsuch as may be powdered by mec anical {means or b making compounds oralloys thereof wit matter of less conductivity, or be it by reducing thetransverse section to cause the solid linear mass to become incandescentand to so produce light. (Compare my Patent No. 523,460, page 2, lines128, &c.)

In the matter of form I declared, among other things and as in specialap licable to the lamp asillustratedherewith, as ollows: The formofaspiral serpentine curve is sim ly one of the innumerable shapes whichmig t be chosen, (compare my Patent N 0.

523,461, pa e 2, lines 54, &c and I described the functional purposes ofthe 02ndbody stratum or film in the luminant-body as a solid bearing inor on its face and interal therewith lines of matter adapted to heat thesolid body by means of the dark heat rays produced by the electriccurrent under adequate resistance. (Compare my Patent No. 566,285, page3, lines 14, &c.) In the matter of material selected applicant has neverwaived his declaration in his Patent No. 621,291, lines 55, &c., namely:I have in all of my preceding applications qualified the current passingand resisting filament by function and not by material. (Compare mypatent No. 621,291, page 1, lines 55, &c.) In corroboration of this mydeclaration the Board of Examiners-in-Ohief in an appeal in the matterof the last-mentioned patent or of the application therefor of October29, 1895, decided as follows: The use of a metal filament was notspecifically mentioned, although the language used was such as toindicate that applicants invention was broad enough to include anymaterlal the equivalent of carbon and having the properties indicated.

In relation to the rare-metal oxlds used 1n some of my improved electriclamps it should be stated that they have by me been qualified mainly asfollows: My improved lamp has a body of solid material, which bodyconslsts of dielectric or non-conductive materlals, which will not fuseat the temperature produced in the lamp and which all or in part arepeculiarly adapted to become luminous, (compare my Patent No. 620,640page 1, lines 66, &c. and in the matter of not using a stratum of\chemical insulation between the primary conductive element and therare-metal oxids in my improved electrical luminants I have adhered tomy declaration as contained in my Patent No. 621,291, page 1, lines 74,&c.,'namely; I ma or may not use an intermediate film that lnsulates thefilament from the coat both electrically and chemically or to one (only)of'these pur oses.

T e fact that metals of the above class have aflinity for oxygenprecludes their use in the eventual presence of oxygen without somemeans of protecting them against oxygenation, and for this I provide achemical insulation consisting of a fine metal hav-.

in virtually no aflinity for ox gennamely go (1, silver, platinum, &c.w'ch is applie 1n the form of a thin coating 2. Such main conductinelement consisting of a core and eventual c emical insulation, such asherein described, may then be embedded in a body 3, constituting theaccessor conductive element above referred to, w 'ch element may consistof rare-metal oxids, the words raremetal oxid being used incontradistinction to the oxidssuch as magnesia, lime,and silicaof metalhaving virtually no afiinity for oxygen or having, as above indicated,materiall less aflinity or oxygen than those of which the core is mainlymade-via, of metals which form solid oxids or such as form ox-' ids asmay be used as surface coating to my luminants, and whichmetals then inthemselves form the rare-metal-oxid body in which the luminant isembedded, becoming,

under the influence of heat generated by the electric current, highlyluminous.

As the metals selected b meto form the core are preferably of highusion-point, difiiculty is encountered in shaping them into thefilaments or core of the roper dimensions, and for overcoming this Ihave devised a method which also forms the subject-matter of thisinvention. In carrying this out I alloy with the selected metal ormetals o the ruthenium osmium class anothenmetal, such as copper or someother one of lower fusionpoint than the point of fusion of theruthenium-osmium metal or alloy, and from such composite alloy of metalsof low and high fusion-point metals shape the core or fila ment. Thishaving been reduced to the desired shape, I eliminate thelow-fusion-point metal. This may be done either by subje ting the coremounted upon a porous base-plate to atemperature suflicient to fuse themetal of lower fusion-point which is absorbed by the base-plate, or Ieliminate the copper or equivalent metal by a chemical reaction in usingor a suitable solvent removing the metal by a suitable diluted acidwhich leaves the highfusion metal or metals unaffected, due to thechemicallyresisting nature of the metals of the ruthenium-osmium class.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-- 1. A luminant for an electric incandescent lamp,being a combination of alloys of metals in layers of higher and lower.ailinity to oxyen, the latter coated on their exposed surface with theirown oxids.

2. A luminant for an electric incandescent lamp, being a combination ofan alloy of metals, having a lLgh point of fusion, brittleness in theirnative state and affinity for .oxygen, and of a covering of an alloy ofrare metals, which have less a'flinity for oxygen, which is coated withtheir own oxide.

3. A luminant for electric incandescent lamps, being a combination ofthe alloys of metals of lL'gher and of lower allinity to oxygen; theformer being an alloy of metals of the ruthenium-osmium class, whichhave a hi h point of fusion, brittleness in their native state, andaffinity for oxygen, and the latter being concentrlcal with but on theoutside of the former being an alloy of so-called rare metals and ofless allinity'for oxygen and coated on their outside with their ownoxids.

4. A luminant for an electric incandescent lamp, being a combination ofconcentrical layers of alloys of metals, the metals o the outside layerhaving less aflinity for oxygen than the metals of the inner layer andbeing in part of their thickness oxidized on the surface, a metallic,chemically-insulating contact with the inner layer being preserved.

5. A luminant for electric incande cent lamps, which consists ofconcentrically-adhering parts, the inner part being an alloy mainly ofmetals of the ruthenium-o.-mium class which combine with a high point offu-.

sion and brittleness in their native s ate, affinity for oxygen, and theouter part, which is exposed to the surrounding space on its entirefilament-shaped surface, consisting of metals of mainly less affinity tooxygen, called rare metals coated with their own oxid.

6. The method of manufacturing luminants for electric incandescentlamps, which consists in preparing a filament of an alloy of metals ofthe ruthenium-osmium lass and in completing a luminant, of filamentshape and exposed to surrounding space with its entire surface, bycoating the filament with other metal-of less affinity for oxygen,called rare metals, and by coating these rare metals on their outersurface with their own oxids thereby forming a combination of 0on5centrical metal and oxid layers in filament shape.

7. The method of manufacturing luminants for electric incandescentlamps, which consists of primarily making a filament of mainly an alloyof metals of the rutheniumosmium class, which combine with alligh pointoffusion and with brittleness in their native state, affinity foroxygen, and hen covering the same with an alloy of meta s of lessallinity to oxygen, called rare metals. and by finally coating thisalloy of rare metals with their own oxids, leaving the surfa e of theluminant exposed to the surroun ing space on its entire exterior therebyforming a combination of concentrical metal and oxid layers in filamentshape.

8. A luminant in an electric incandescent lamp, which consists of apermanent metal alloy core, covered with a film of other metal of lessallinity for oxygen than the metal of the core.

9. A luminant or filament in an electric incandescent lamp, whichconsists of a plurality of permanent layers of different metal alloys,composed of metals of a different degree of affinity for oxygen, thealloy composed of metals of least affinity for oxygen being upon theoutside.

10. A luminant or filament in an electric incandescent lamp, whichfilament consists of a plurality of layers of different metal alloys,which alloys are composed of metals, that have different degrees ofaflinity for oxygen, the central alloy of which is composed of the moreoxygenatable and more infusible metals.

11. In the luminant of an electric incandescent lamp a conductiveelement or filament, which consists of metal alloy, having a'llinity foroxygen and a high point of fusion, coated with metal of less aflinityfor oxygen.

12. A luminant for an electric incandescent lamp, which consists of aconductive filament of layers of different metal alloys, and of acoating thereon of rare-metal oxids.

13. In a luminant for an electric incandescent lamp a filament, whichfilament consists of a metallic core havinga high oint of fusion andaffinity for oxygen, and of an electrolytic plating thereon of a metalalloy, having little aflinity for oxygen, the whole being embedded inrare-metal oxids. 14. The combination in a luminant for an electricincandescent lamp, of a core of metal alloy, the component metals ofwhich alloy have affinity for oxygen and high points of fusion, and ofan insulating coat therefor, and of a surrounding light-emitting body.

FRANCIS M. F. CAZIN.

Witnesses:

ADELE CAZIN, O. K. CAzIN.

